Traditionally recognized every May 30th to pay tribute to America’s fallen soldiers, Memorial Day was officially designated a federal holiday in 1971, now celebrated on the last Monday of May.

Businesses increasingly have chosen to stay open, leading to what is now one of the biggest retail sales and travel weekends of the year.

Here’s what is open and closed this year on Memorial Day:

GOVERNMENT BUILDINGS

Government offices, post offices, courts and schools are closed.

BANKS AND MARKETS

U.S. stock markets and banks are closed Monday.

Most FedEx and UPS pickup and delivery services will also not be available on Memorial Day, though some special services will be accessible.

RETAILERS

The warehouse membership store Costco will not operate on Memorial Day, whereas most other retailers will remain open, with many attempting to attract customers through significant promotional sales. Operating hours may differ based on location.

TRAVEL

Memorial Day is also regarded as the unofficial start of the summer travel period. Americans are anticipated to travel in unprecedented numbers throughout the extended Memorial Day weekend despite economic and technological challenges affecting the U.S. travel sector.

Auto club AAA projects that more than 45 million people — 1.4 million more than last year — will venture at least 50 miles from their homes between Thursday and Monday, with the vast majority going by car. The holiday’s previous domestic travel record of 44 million people was set 20 years ago.

AAA’s fuel tracker shows motorists can expect to pay less for gasoline this year. The U.S. average price on Wednesday was $3.18 for a gallon of regular gas compared to $3.60 a year ago.

AAA projects 39.4 million people will travel by car over the weekend — the highest number for that holiday since AAA began tracking it in 2000 — and that another 3.61 million people will travel by air, a nearly 2% increase over last year’s 3.55 million.

Air safety has been on the minds of travelers after a midair collision in January of a passenger jet and a U.S. Army helicopter above Washington, D.C. killed 67 people. There have also been some close calls.

In recent weeks, flight delays and cancellations stemming from an air traffic controller shortage and equipment failures at a facility that directs aircraft in and out of the Newark, New Jersey, airport have also made some people reluctant to get on a plane.